电感耦合等离子体质谱法测定环境样品中超痕量^(239)Pu的^(238)UH^+谱线干扰研究  

Study on the Interference of ^(238)UH^+ Spectrum in the Determination of Ultra-trace Amount of ^(239)Pu in Environmental Sample by ICP-MS

作　　者：韩小元[1] 王江[1] 田梅[1] 张瑞荣[1] 卓尚军[2] 

机构地区：[1]西北核技术研究所,西安710024 [2]中科院上海硅酸盐研究所,上海200050

出　　处：《理化检验（化学分册）》2013年第4期377-381,385,共6页Physical Testing and Chemical Analysis(Part B:Chemical Analysis)

摘　　要：环境样品中239 Pu的含量非常低,即使经过基体放化分离,238 UH+复合离子对239 Pu的干扰仍然很严重,直接扣除干扰谱线信号对分析结果的准确度影响较大。从仪器物理测量的角度研究了降低238 UH+复合离子产率的方法,包括进样系统、激发系统和离子界面层。研究结果表明,膜去溶装置可降低238 UH+复合离子产率一个数量级以上。射频功率对238 UH+复合离子的产率有一定的影响。在雾化气流速最佳的条件下,238 UH+复合离子产率达到最小值。Xs锥测量238 UH+复合离子产率的结果相对采用Xt锥的测量结果略低一些。Owing to the extracrdinary low-content of 239Pu in environmental samples, serious interference of the hydride ion. 238UH＋ to 239Pu in its ICP-MS determination was still encountered even after radio chemical separation of the matrix; and remarkable effect to the accuracy of analytical results was found by the simple and direct deduction of signal intensity of the interfering spectrum from the signal intensity of the analyte. As shown by the experimental results of the study of physiad measurements of the instruments in vriw to lower the rate of formation of 238UH＋ , the rate was lowered to more than one order of magnitude when membrane de-solvation installation was used in the nebulizer; the RF power showed only little influence on the formation rate; under the optimum flow rate of nebulizer gas, the formation rate of 238 UH＋ attained to its minimum. Values of the formation rate of 238UH＋ measured by Xs skimmer cone was found to be a little lower than those measured by Xt skimmer cone.

关 键 词：电感耦合等离子体质谱法 239Pu 238UH+ 238UH+离子产率 

分 类 号：O657.6[理学—分析化学]